I had this exact same issue a few months back. Turns out my problem was that the screws on the dimmer switch had come loose. It caused the rod that goes from cruise control lever that you pull back to turn on the high beam to sit in the dimmer switch the wrong way. Every single light came on in my car and the outside except for the regular headlights, the high beams worked but wouldn't stay on, they'd just flicker as I moved the cruise control/ turn signal lever. Because the dimmer switch wasn't lined up with the rod that goes down the side of the steering column right, it caused my regular headlights not to work. Only thing I did was readjust it and put a little loc-tite on the screw so that they wouldn't come loose again over time. Didn't even have to get a new dimmer switch. Hope this help.